The arrow shows the route for the first summer crossing of the Arctic Ocean. By kayak and on skis, with no external support, Lonnie Dupre and Eric Larsen will leave Siberia in May 2005 and travel via the Pole, expecting to reach Canada 100 days later. The white area indicates the ice cap in September 2003. The pale blue area shows how far it extended in September 1979. During this period the summer ice cap decreased by about 18 per cent.